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Bacteria

Bacteria. BACTERIA. Bacteria (Monerans)– Kingdoms Archaebacteria and Eubacteria. There are more bacteria on Earth than stars in the sky! The closest estimate is that there are 5 million trillion trillion bacteria on Earth – that’s a 5 with 30 zeroes after it.

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Bacteria

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  1. Bacteria BACTERIA

  2. Bacteria (Monerans)– Kingdoms Archaebacteria and Eubacteria • There are more bacteria on Earth than stars in the sky! • The closest estimate is that there are 5 million trillion trillion bacteria on Earth – that’s a 5 with 30 zeroes after it. • Bacteria produce the air we breathe, clean the water we drink, and create fertile soil. • Less than one percent of bacteria cause diseases.

  3. Bacteria structure – prokaryotic cell plasmid

  4. Bacteria Growth Curve

  5. Most bacteria die when conditions get bad: • These conditions could be a change in temperature, loss of food, change in pH, etc. • Some bacteria can preserve themselves during bad times, then they can regrow and resume their lives. They do this by producing an endospore. • Endospores can preserve the cell’s DNA until conditions get better again. They are resistant to all the bad conditions.

  6. Endospore production – preserves the cell during hard times– not a form of reproduction • Steps in formation of an endospore

  7. Endospore Bacteria that are harmful to humans and that form endospores: Clostridium tetani –causes tetanus Clostridium botulinum –causes food deadly poisoning

  8. Binary Fission – bacteria can divide as often as every 20 minutes!

  9. Origin of Monerans • Archaebacteria • usually found in harsh environments – hot, salty, smelly! • Ancient – probably resemble the first bacteria

  10. Methanogens • produce methane – live in digestive tract of mammals, in swamps and sewage.

  11. thermophiles • can live in extremely hot water – found in hot springs

  12. halophiles • Live in very salty water, such as the Great Salt Lake in Utah and the Dead Sea

  13. Eubacteria – true bacteria • Many types – modern bacteria • Classification is by: • Cell shape • Cell wall composition • Nutrition • Respiration

  14. Cell Shape Coccus - round Bacillus - rod spirillum

  15. Names can tell a lot about the bacterial growth • Some bacteria grow alone • Diplo…means two • Diplococcus • Diplobacillus or • Strepto… means chain • - as in streptococcus • - and streptobacillus • Staphylo… means cluster • As in staphlyococcus

  16. Cell Wall Composition – gram positive or gram negative • Gram PositiveGram negative • Stains bluestains pink

  17. Nutrition – Autotrophic or Heterotrophic • Autotrophs – • make their own food • Use sun’s energy or chemical energy

  18. Most Monerans are Heterotrophs Escherichia coli spirillum anthrax

  19. Respiration – process of getting energy from food Aerobic • Need oxygen • Can’t live without oxygen = obligate aerobes • EX – TUBERCULOSIS BACTERIUM • Prefers to live with oxygen = facultative aerobes Tb lung

  20. Anaerobic – • don’t need oxYgen • SOME CAN’T SURVIVE WITH OXYGEN – THESE ARE OBLIGATE ANAEROBES EX – TETANUS This baby probably got tetanus from honey – don’t give honey to a baby!

  21. SOME CAN LIVE WITH OXYGEN BUT PREFER TO LIVE WITHOUT IT – fACULTATIVE ANAEROBES E. coli

  22. How Important are bacteria to the world? • Decomposition – most important function for living things. What happens to all the dead bodies? • Here is a bacterium of decay

  23. Food web

  24. Nitrogen cycle

  25. Cow Digestion Bacteria in the stomach

  26. Tooth Decay Don’t forget to brush and floss your teeth!

  27. Foods from bacteria cheese yogurt sauerkraut

  28. What conditions do bacteria need for the best growth? • Food source (your soup is good) • Proper temperature - human pathogens (disease causers) live best at 98.6 F. • Moisture • Oxygen (aerobes) or not (anaerobes) Change any of these and the growth of bacteria can be slowed down or stopped.

  29. We compete with bacteria for our food – they eat the same stuff we do…. How do we preserve our food? Drying (prunes) salting refrigeration pickling freezing

  30. Diseases caused by bacteria Anthrax – a natural pathogen that can be used for bioterrorism

  31. Lyme disease – causes illness and can lead to arthritis

  32. gonorrhea plague Strep throat

  33. Food poisoning Salmonella food poisoning – from eggs, chicken, mayonnaise Botulism – from improperly canned foods

  34. Antibiotics, if used cautiously, can cure bacterial infections

  35. Antibiotics are tested using Petri dishes and paper soaked in the antibiotic – anywhere the antibiotic inhibits growth, a zone of inhibition will be seen Most effective Not effective

  36. Here is a white blood cell attacking a bacillus bacillus

  37. Uses of bacteria other than food production • Bioremediation – using microorganisms to rid environment of harmful substances • Ex – oil spill site • Hazardous waste site • Sewage treatment

  38. Medical uses of bacteria • Genetic engineering to produce medical products – • Insulin • Human growth hormone Gene for human insulin or hgh Now all cells will have the gene and will make the product

  39. That’s all folks!

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